The formula of a trapezoid is A=1/2h(b1+b2)

Express b1 in terms of A,h,and b2

I did A=1/2hb1+1/2hb2
A=hb1/2 +hb2/2

A-hb2(2/h)=hb1/2(2/h)
A-b2=b1

I am not sure if this is correct? I was confused on how to do this. Any help or explanation is greatly appreciated. Thank you.

1 answer

A = (b1+b2)h/2
(b1+b2)h = 2A
b1+b2 = 2A/h
b1 = 2A/h - b2

you forgot to multiply A by 2/h